This code means there is a problem in the transmission gear selection switch circuit. This issue can be repaired by an automatic transmission repair shop which is familiar with electronic transmission controls; or by an Acura dealership. However, I would not go to AAMCO or any other transmission repair chain that advertises on TV.
This is not a common problem; and many shops would not be familiar with the repair procedure. It might be that the dealership is the best choice for the repair; as they have all the diagnostic instructions in their service manuals.
Prices for such a repair can vary greatly; both between different shops, and in different parts of the country; so you will get a much more accurate estimate by phoning local shops and dealerships than by asking us.